Make sure you are using Soul Leech. I also recommend playing a GoSac as Destruction. Also, make sure you are glyphed to reduce the cast time of Enslave Demon. Next, set up your Gateway so that it reaches behind the pillar on the right side of the portal in which the boss comes. I would also recommend you put your Demonic Circle in the same location.

Macros that will help:

/cast [target=mouseover] Havoc
(Use this to get double Chaos Bolts into the felhounds)

/cast [target=Pit Lord] Enslave Demon

Now, your enslaved Pit Lord should take over on threat but be sure that you kill the felhounds quickly or they will remove your enslavement. You will at one point have to re-enslave the Pit Lord. Make sure you use the Pit Lord's heal on you wisely, though its cooldown is not too long. Use the Pit Lord's flame breath on the imps that spawn. Also, I would recommend taking Mannoroth's Fury and using it for the Imps and Felhounds. Be sure you are wary of the bosses Chaos Bolts and only using the Pit Lord's interrupt on Cataclysm.

*Note* This fight becomes exponentially easier with gear. I didn't even attempt this fight until I was at least 520 ilevel and I two shot it I believe. I would recommend (with not know your current gear) getting as much gear from the Timeless Isle as possible, LFR, or Flex before attempting. It can be done at very low gear levels but you have to be mistake free, essentially. I hope this helps in anyway and good luck!

I'm getting real frustrated with this fight, anything goes wrong and you're dead and him being on me does not help. So, you're saying I should gateway whenever it's up?

That's the core reason of why this fight is(or was) so awesome. cuz its unforgiving around mistakes.
but about aggro gateway doesn't work that way right? soul shatter must work, I used soul shatter mostly when he summd doomguards cuz I didn't want to move my ass out of his ass with using gateway. but it was before 5.4. but I did have some tries on him without using gateway anyhow and just using portal for LOS CB. this must work if you care much about it and practice it. I didn't care cuz I could reset aggro with soul shatter/gateway :P

If they changed chaos bolt and gate debuff interaction that sucks. What you can do is use the los strat to deal with chaos bolts and obviously just get gear. With the enormous ilvl jump this tier he should be faceroll with any strat.

To add to this, sac an IMP. That dispel is really useful for the times where you need to be as far away from the pit lord as possible. Getting a bad black hole or annoying imps debuff, especially the imp debuff, is just SO annoying.

I've done this fight with ilvl 470 and not having the pet tank the boss so it is very possible, hang in there.

Just be sure to LoS the Chaos Bolts. And try to stand in front of the pit lord and do his flame breath when you have dots. This fight can easily be out geared now. I was lazy and didn't do mine till 540 ilvl. To put this in perspective, that is a mix of RF/Flex gear basically. If you are doing any normal or heroic kills in Siege you will be far above the point you can just use brute force. I killed him right as he was summoning the doom guard. Took maybe 10-15 attempts total. Had some very painful low wipes for RNG reasons before the kill.

The tooltip is wrong, it was changed when 5.4 hit. Would be pretty broken if all you had to do at the start of any boss fight is have all of your high dps jump through a gateway to get a 1 min no threat gen debuff.

Green Fel Fire Last boss.....

So, I don't understand something... Is the last boss for the green fire bugged or something? Because everytime I come to the Felhunter phase it dispels my enslave EVEN THOUGH my pit lord is literally 200 yards away and LoSed (not joking, I actually measured it). I have full aggro on the Fel hunters and almost no issues with the rest of the fight. I CANNOT get past this phase though because of that reason. I've wiped 37 times now, all at the same spot, all with the same problem.

Maybe a patch bug or something? Idk. When you've LoSed your pitlord in every tangable spot and it still get purged, then something is wrong.

I just did the fight for a second time (Alliance warlock this time, lol) about a week or two ago and experienced no issues like this.

Just in case you're not doing it, the felhunters *must* face away from the pit lord. Once I kept them facing away from him I never had an enslave get dispelled again. LoS never worked for me, they literally had to be facing the opposite direction of the PL.

What I personally did was let the pit lord stay on Kanrethad while I moved behind the big gateway before they spawn. When the felhunters come out, I had a rain of fire ready, hit them with shadowfury, popped dark soul and havoc'd a chaos bolt onto 1 and 2, then burned them down the rest of the way.

Yeah. In my first attempts back on my Horde warlock I was using the tactic of moving the pit lord to the other side of the room, then running to the opposite side to deal with the felhunters. They still chain dispelled the enslave.

From watching someone's video while frustrated I noticed they didn't move the pit lord away but instead went behind the gateway to dps them down and a light bulb went on.

Good luck, let us know if that works! If not, it very well might be a patch-related bug, who knows?

Yeah. In my first attempts back on my Horde warlock I was using the tactic of moving the pit lord to the other side of the room, then running to the opposite side to deal with the felhunters. They still chain dispelled the enslave.

I did the same. You just need a lot of burst to kill the felhunters before the Pitlord arrives you.

I did the same. You just need a lot of burst to kill the felhunters before the Pitlord arrives you.

It certainly works, but it's easier to just turn them away from him and nuke them down....that way you can re-enslave the pit lord at the time of your choosing. For me that was usually right before the doom guard/lord came out.

First pull with 540ilvl gear starts at 3:45. I then removed some gear to somewhat match his stats ( ilvl down to 466 ), and fixed my WeakAuras to show the Agony debuff and tried again, starts at 12:10.

Continue moving a bit backwards when the felhunters are up and while you nuke them down. I had them turn around many times myself when I just stood still, as mobs often do when trying to get into the right position.

Kite the Pit Lord and the Fel Hunters until the Fel Hunters are dead. I do it that was as Demonology with no issues at all, and I've done it with as low as a 460 ilvl and still killed the Fel Hunters and enslaved the Pit Lord before Cataclysm was cast.